Any time there’s a cold snap, my brother races madly around his house until just about every faucet in the place dripping. We all abide by this ancient practice because we’ve been told it will save our pipes from freezing. And there’s good reason to worry about that: A frozen water pipe can burst, and that can mean some really expensive damage. While repairing the pipe itself is often not so bad—it’ll run you anywhere from $200 to $1,000—the real culprit is the water damage that occurs when things thaw and water soaks your house.
But many of us have been letting our faucets drip every winter without ever pausing to wonder whether it actually works, or if it’s one of those old-timey pieces of wisdom that was never quite true in the first place. The good news is that yes, letting a faucet drip can help prevent burst pipes. But like everything else in life, it’s a bit more complicated than that.
How to let your faucets drip in cold weather
There are four basic things you need to know about leaving a faucet dripping in cold weather:
1. Letting your faucet drip will not stop your pipes from freezing. While letting the water flow can slow down the process a bit by allowing warmer water to enter the home regularly (no matter how cold the air is outside, the water pipes coming into your house from underground are insulated by the earth and are probably a lot warmer), water freezes whether it’s moving or not. That means if it’s cold enough, and water can and will freeze in your pipes even if you have a faucet dripping if the temperature drops and stays low for a long enough period. So why do we let the faucet drip? Because it can prevent your pipes from bursting, my friends. When the water in your pipes freezes, it expands, stressing your pipe. If you have all the faucets closed when the water starts to melt, it will have nowhere to go, so it will soon create somewhere to go. Having a faucet open gives that water a release point, which can save your pipes.
2. Second, you don’t need to leave every faucet in your home dripping. Ideally, you should locate the faucet that’s farthest away from where the water enters your home. This way the water flow can help the entire infrastructure. If you’re not sure where the water is entering your house, select any faucet—it will be better than nothing.
3. The word “drip” is vital here. There’s no need to have a steady stream of water—a very slow drip will do the job. You should also consider capturing your dripping water in a bucket or other container instead of just letting it waste down the drain—you can use that water for filling up filtered water pitchers, or for washing dishes, watering plants, or any other water-based activity.
4. Finally, if your pipes freeze despite a dripping faucet, don’t turn off the faucet. Leave it open so the water has a place to go when the thaw comes. This is also a very good time to turn off the water at the main and take some steps to protect your property and possessions in order to minimize the damage that might come with a burst pipe.